Chinese Acad Sci, Inst High Energy Phys, Beijing Synchrotron Radiat Lab, Beijing 100039, Peoples R China
; IIT, Dept Biol Chem & Phys Sci, Chicago, IL 60616 USA
; Beijing Inst Technol, Coll Chem Engn & Mat Sci, Beijing 100081, Peoples R China
Article; Proceedings Paper
Hematite nanoparticles which were coated, respectively, with sodium dodecyle benzene sulphonate (DBS) and cetyltrimethyl ammnonium bromide (CTAB) were synthesized by using microemulsion method in the system of water/toluene. The particle size and shape were characterized with transmission electron microscopy (TEM). The TEM results show that the nanoparticles take the shape of sphere with diameter of 5.0 mm and 6.0 nm for modified DBS and CTAB respectively. The local atomic structures of these nanoparticles were probed by using XAFS technique. Fe-K absorption spectra were collected at beam line 4W1B of BSRF. The local atomic structure in DBS-coated hematite was found to be similar with that in bulk hematite except the anharmonicity increasing, but about 0.04 Angstrom expansion of Fe-O bond length in CTAB-coated hematite. The interface/surface atomic configuration were compared and discussed.